Variant Creutzfeldt–Jakob disease

Some people get a brain sickness.

It can come from eating bad beef. This sickness is caused by tiny parts in the brain. These parts are shaped wrong.

It can change how a person acts. It can make it hard to move well. It can also cause pain.

Most people get sick before they are 30. It can take many years to start. Doctors look at the brain to find it.

This sickness is very serious. We study it to stay safe.

Some people get a brain sickness called vCJD.

This sickness is caused by prions. Prions are tiny parts of a protein that are shaped wrong. These prions can make other proteins change shape too.

Many people got sick from eating beef. This beef had a sickness called BSE. Some people think it may also spread through blood. It can even spread if a person touches infected brain during work.

The sickness can change how a person acts. It might cause pain or mood changes. Later, it can make moving hard. It can also cause dementia, which is a loss of memory. Most people get sick before they are 30 years old. It can take many years for symptoms to show up.

Doctors use a brain biopsy to find the sickness. A biopsy is when doctors take a tiny piece of tissue to study it. This disease is very serious. On average, people live for 13 months after they feel sick.

Variant Creutzfeldt–Jakob disease, or vCJD, is a very serious brain sickness.

It belongs to a group of illnesses called transmissible spongiform encephalopathies. This name describes how the disease affects the brain. People sometimes call it "mad cow disease" to distinguish it from the version found in animals. vCJD is fatal, which means it cannot be cured. It affects the way the brain works and how people behave.

The disease is caused by tiny things called prions. Prions are proteins that are misfolded, meaning they are shaped the wrong way. When these misfolded proteins enter the body, they can cause other proteins to change shape too. This happens mostly when people eat beef infected with BSE. BSE is a disease found in cattle. It is believed that humans also face risks from blood products or dirty surgical tools.

Scientists first identified vCJD in 1996. This discovery was made by the National CJD Surveillance Unit in Edinburgh, Scotland. Before this, a researcher named Harash Narang suggested a link between BSE and CJD in 1989. The disease was more common during an outbreak in the 1990s. Since the year 2000, the disease has become much less common. As of 2020, 178 cases were recorded in the United Kingdom. There were also 50 cases found in the rest of the world.

Symptoms of vCJD can change as the sickness progresses. At first, a person might have mood changes or feel painful sensations. Later, they may experience dementia, which is a loss of memory and thinking skills. They might also have trouble moving or have involuntary movements. Most people who get vCJD are less than 30 years old. It can take many years for symptoms to appear after someone is exposed. On average, people live for 13 months after symptoms start.

Many countries have made rules to keep people safe from this disease. For example, Japan and Canada once banned beef from the United States. Many places also have strict rules for donating blood. In the United Kingdom, people who had blood transfusions after 1980 cannot donate blood. New Zealand and Canada also had rules about where people lived to protect their blood supplies. These rules help prevent the spread of prions through medical treatments. Scientists continue to study the disease to understand it better.

Variant Creutzfeldt–Jakob disease, often called vCJD, is a fatal brain disorder. It belongs to a group of illnesses known as transmissible spongiform encephalopathies. This family of diseases affects the brain's structure and function. While people sometimes call it "mad cow disease," that term is usually used to describe the animal version, bovine spongiform encephalopathy (BSE). vCJD is a distinct human condition. It is a very serious illness that leads to death.

The disease is caused by prions. Prions are proteins that have become misfolded, meaning they are shaped incorrectly. When these abnormal proteins enter a healthy body, they can cause normal proteins to change shape as well. This creates a chain reaction of misfolding. In the United Kingdom, the primary cause of vCJD is eating beef infected with BSE. This happened because cattle were fed meat and bone meal containing protein from other animals. This human decision allowed an animal pathogen to enter the human food chain.

Symptoms of vCJD change as the disease progresses through different stages. The initial stage often involves psychiatric problems and behavioral changes. Patients may also experience painful sensations during this early period. As the illness reaches later stages, it affects physical and mental abilities. Patients may develop dementia, which is a loss of memory and thinking skills. They might also suffer from poor coordination and involuntary movements. Most people diagnosed with vCJD are under 30 years old. After symptoms appear, the average life expectancy is only 13 months.

Scientists have worked for years to understand the history of this disease. The National CJD Surveillance Unit in Edinburgh, Scotland, first identified vCJD in 1996. However, research by virologist Harash Narang suggested a link between BSE and CJD as early as 1989. The disease was much more common during an outbreak in the 1990s. Since the year 2000, the occurrence of vCJD has become much less common. As of 2020, there were 178 recorded cases in the United Kingdom. There were 50 cases recorded in the rest of the world.

There are several ways the disease might spread beyond eating tainted beef. Evidence suggests that prions may be present in the blood of people with vCJD. This is different from sporadic CJD, where prions are not typically found in the blood. Because of this, vCJD can be transmitted through blood transfusions. This discovery caused great concern for healthcare officials. There is also a risk of occupational contamination in laboratories. In France, two research technicians died after being pricked by tools contaminated with infected brain.

Because of these risks, many countries have implemented strict safety rules. Many nations, including Japan and Canada, once banned beef imports from the United States. In the United Kingdom, anyone who received a blood transfusion after January 1980 is banned from donating blood. New Zealand and Canada also had strict rules regarding where donors had lived. These rules were designed to protect the blood supply from prions. While some countries have recently removed these restrictions, they were vital for preventing a larger epidemic.

Understanding the genetics of vCJD helps scientists explain why some people get sick while others do not. The human PRNP protein is the part of the body that prions affect. This protein can have different forms based on amino acids at a specific position. Most people with vCJD have two copies of a methionine-containing form of this protein. Only one tested patient was found to be heterozygous, meaning they had different forms. This suggests that certain genetic traits might influence how a person responds to the disease. Researchers are still studying if these genetic patterns provide actual immunity.